GDUKOP Engine Coolant Overflow Reservoir Tank 603-955 for Buick Encore & Chevy Trax — Heat-Resistant Plastic with Cap

GDUKOP 603-955 is a direct-replacement engine coolant overflow reservoir tank with cap engineered to restore proper coolant containment and level monitoring for specified Buick Encore and Chevy Trax models.

This replacement coolant overflow reservoir tank from GDUKOP is designed to match OE fit and function for select Buick and Chevy compact SUVs. Manufactured from heat-resistant plastic and finished with a matching cap, it replaces worn or cracked tanks that can lead to coolant loss, visible leaks, or inaccurate reservoir readings. The unit ships ready for installation and aligns with original mounting points and hose connections for a straightforward swap.

Will this reservoir fit my vehicle?

The GDUKOP 603-955 reservoir fits specific model years and engine sizes without modification. Verify your vehicle's model year and engine code before ordering to ensure compatibility.

• Compatible with Buick Encore 2013–2021 L4 1.4L
• Compatible with Chevy Trax 2013–2021 L4 1.4L and 2013–2019 L4 1.8L
• Replaces OE numbers 603-955, 13502353, 95201979, 95269001

How durable and reliable is the replacement tank?

GDUKOP builds this reservoir from durable, heat-resistant plastic formulated to withstand engine-bay temperatures and chemical exposure. The material resists cracking and warping so the tank can maintain pressure boundaries and fluid containment over time.

• Heat-resistant polymer construction minimizes thermal degradation
• Designed to resist coolant chemical exposure and stress cracking
• Factory-style wall thickness and mounting points for long-term stability

Is installation difficult and what tools are needed?

Installation is intended to be straightforward because the tank is engineered as a direct replacement for the factory unit. Most DIYers with basic hand tools can complete the swap in a short session; however, follow vehicle-specific guidance and safety precautions when working with coolant.

• Direct-fit design aligns with original mounting tabs and hose connections
• Common tools: pliers, screwdrivers, socket set, coolant catch pan
• Drain and refill coolant per vehicle manual to avoid air pockets

What performance benefits should I expect after replacement?

Replacing a compromised reservoir helps maintain proper coolant level monitoring and containment, reducing the chance of visible leaks and improving system consistency. While it doesn’t change engine performance by itself, a healthy reservoir supports the cooling system’s ability to regulate temperature effectively.

• Restores sealed overflow containment and accurate level readings
• Reduces risk of coolant loss from cracks or failed fittings
• Supports consistent coolant circulation and temperature regulation

Who is this for: The GDUKOP 603-955 reservoir tank is aimed at owners of compatible Buick Encore and Chevy Trax models who need a reliable, OEM-style replacement. It’s suitable for mechanics, DIY enthusiasts, and fleet maintenance teams seeking a cost-effective, durable part that simplifies installation and restores the cooling system’s proper operation.